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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

4055 results found.

  1. LIGO/VIRGO G184098: Summary of VLA results for iPTF15cyk
  2. LIGO/Virgo G184098: MASTER final result
  3. LIGO/Virgo G211117: Refined localization from CBC parameter estimation
  4. LIGO/Virgo G211117: Preliminary VLA observation summary of PS15dpn
  5. LIGO/Virgo G211117: Further Swift-XRT sources
  6. LIGO/Virgo G211117: INAF NOT follow-up of PanStarrs candidates
  7. LIGO/Virgo G184098: Refined localizations from CBC parameter estimation
  8. LIGO/Virgo G211117: Updated FAR estimate based on offline re-analysis
  9. LIGO/Virgo G184098: Updated FAR estimate
  10. LIGO/Virgo G211117: Distance estimate from GW data compared to redshift of PS15dpn
  11. LIGO/Virgo G211117: Swift observations of PS15dpn
  12. LIGO/Virgo G211117: iPTF Observations of PS15dpn
  13. LIGO/Virgo G211117: PESSTO classification of MASTER J165420.77-615258
  14. LIGO/Virgo G211117: VLA follow-up
  15. LIGO/Virgo G211117: Pi of the Sky observations
  16. LIGO/Virgo G211117: VISTA imaging
  17. LIGO/Virgo G211117: Subaru Hyper Suprime-Cam follow-up observation
  18. LIGO/Virgo G211117: MASTER OT in ESO138-006 galaxy
  19. LIGO/Virgo G211117: Further Swift-XRT sources
  20. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  21. LIGO/Virgo G211117: Summary of Pan-STARRS transients
  22. LIGO/Virgo G211117: INAF TNG follow-up of Kanata telescope candidate
  23. LIGO/Virgo G211117: Fermi/LAT observations
  24. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  25. LIGO/Virgo G211117: Gemini classification of 7 Pan-STARRS transients
  26. LIGO/Virgo G211117: LOFAR follow-up
  27. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  28. LIGO/Virgo G211117: PESSTO classification of Pan-STARRS transients
  29. LIGO/Virgo G211117: MASTER OTs 26.XII.2015 - 01.I.2016
  30. LIGO/Virgo G211117: CSS/CRTS observations on 29/30 Dec 2015 UT
  31. LIGO/Virgo G211117: La Silla - QUEST observations 2015 Dec 28 - 30
  32. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  33. LIGO/Virgo G211117: FLOYDS Classification of SMTJ13331687-1607330 as a Two-Week-Old Type Ia Supernova
  34. LIGO/Virgo G211117: LBT follow-up imaging of iPTF15fhq
  35. LIGO/Virgo G211117: 44 transients from Pan-STARRS data during 2015-12-28/30
  36. LIGO/Virgo G211117: MAXI/GSC observations
  37. LIGO/Virgo G211117: Liverpool Telescope followup of EM candidates
  38. LIGO/Virgo G211117: VLA follow-up
  39. LIGO/Virgo G211117: LBT Follow-up of iPTF15fen
  40. LIGO/Virgo G211117: MAGIC very-high energy gamma-ray observations
  41. LIGO/Virgo G211117: INAF TNG follow-up of MASTER OT J020906.21+013800.1
  42. LIGO/Virgo G211117: OAO-WFC NIR follow-up observations
  43. LIGO/Virgo G211117: SkyMapper observations and transient candidate
  44. LIGO/Virgo G211117: MASTER Observations of the 3 iPTF candidates
  45. LIGO/Virgo G211117: Optical Observations with Kiso Schmidt telescope and KWFC
  46. LIGO/Virgo G211117: List of near-term future observation regions by Project Mini-GWAC of SVOM
  47. LIGO/Virgo G211117: iPTF Optical Transient Candidates
  48. LIGO/Virgo G211117: La Silla - QUEST observations 2015 Dec 28, 29
  49. LIGO/Virgo G211117: Further Swift-XRT sources
  50. LIGO/Virgo G211117: DESGW program observations with DECam
  51. LIGO/Virgo G211117: Optical NIR observation with Kanata telescope
  52. LIGO/Virgo G211117: Fermi GBM Observations
  53. LIGO/Virgo G211117: Optical follow-up with Kanata telescope
  54. LIGO/Virgo G211117: MASTER Observations and Inspection + OT
  55. LIGO/Virgo G211117: INTEGRAL was inactive at the time of the event
  56. LIGO/Virgo G211117: Pan-STARRS1 observations 2015-12-28
  57. LIGO/Virgo G211117: INAF VST-ESO PARANAL observations
  58. LIGO/Virgo G211117: Further Swift-XRT sources
  59. LIGO/Virgo G211117: Swift-XRT sources
  60. LIGO/Virgo G211117: SWASP optical observations
  61. LIGO/Virgo G211117: MASTER possible OT detection at the begining of inspection
  62. LIGO/Virgo G211117: Identification of a GW CBC Candidate
  63. LIGO/Virgo G184098: Fermi-LAT search for high-energy gamma-ray counterpart
  64. LIGO/Virgo G184098: LOFAR follow-up
  65. LIGO/Virgo G184098: Results of of 2nd epoch of ASKAP follow-up
  66. LIGO/Virgo G194575: Updated significance from offline GW analysis
  67. LIGO/Virgo G194575: Fermi GBM Observations
  68. LIGO/Virgo G194575: VLA follow-up
  69. LIGO/Virgo G194575: Liverpool Telescope observations of iPTF-15dld and iPTF-15dni
  70. LIGO/Virgo G194575: La Silla QUEST, Pan-STARRS and PESSTO observations of iPTF15dld
  71. LIGO/Virgo G194575: Swift observations if iPTF15dld
  72. GRB 151027A: Hankasalmi optical observations
  73. LIGO/Virgo G194575: INAF-TNG/Asiago Telescope follow-up of iPTF15dld
  74. LIGO/Virgo G194575: INAF-Asiago Telescope further analysis of iPTF candidates
  75. LIGO/Virgo G194575: INAF-Asiago Telescope follow-up of iPTF candidates
  76. LIGO/Virgo G194575: VLA follow-up
  77. LIGO/Virgo G194575: MAXI/GSC further analysis
  78. LIGO/Virgo G194575: LT Spectroscopy of iPTF-15dmk
  79. LIGO/Virgo G194575: LT Spectroscopy of iPTF candidates
  80. LIGO/Virgo G194575: INAF-TNG follow-up of iPTF15dkm and iPTF15dlj
  81. LIGO/Virgo G194575: VLA follow-up
  82. LIGO/Virgo G194575 : RATIR Observation of La Silla - QUEST Candidate
  83. LIGO/Virgo O1 extended until January 12
  84. LIGO/Virgo G194575: iPTF Optical Transient Candidates
  85. LIGO/Virgo G194575: MASTER Optical Inspection
  86. LIGO/Virgo G194575: Swift observations of LSQ15bjb
  87. LIGO/Virgo G194575: INAF-TNG spectra of LSQ15bjb
  88. LIGO/Virgo G194575: GROND multi-color observations
  89. LIGO/Virgo G194575: further Pan-STARRS observations of the RA=1hr localisation region
  90. LIGO/Virgo G194575: ASKAP followup
  91. LIGO/Virgo G194575: INAF-TNG follow-up of LSQ15bjb
  92. LIGO/Virgo G184098: VLA follow-up of iPTF15cyk
  93. LIGO/Virgo G194575 : La Silla - QUEST followup
  94. LIGO/Virgo G194575: Near-infrared follow-up with OAO-WFC
  95. LIGO/Virgo G194575: Kanata/J-GEM optical follow-up
  96. LIGO/Virgo G194575: Pi of the Sky observations
  97. LIGO/Virgo G194575: MAXI/GSC observations
  98. LIGO/Virgo G194575: Swift observations
  99. LIGO/Virgo G194575: CQUEAN/LOAO observations
  100. Possible Fermi-LAT Gamma-ray counterpart for LIGO/Virgo G194575

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